The ruling Catalan separatist coalition has said the regional parliament will hold a meeting on Thursday which many fear will become a cover for a vote on declaring independence from Spain.

Catalan president Carles Puigdemont has asked the parliament to convene a debate and vote on how to respond to the central Spanish government's plan to take direct control of the north-eastern region.

Mr Puigdemont's speech on Saturday was seen as a veiled threat of formalising an ambiguous declaration of independence earlier this month that he declared suspended in order to earn time for negotiations.

The Spanish government said that no dialogue is possible with independence on the table and is manoeuvring to sack all the Catalan top officials and call a snap regional election in the next six months.

Spain's political parties have designated 27 senators to study how the government might intervene in the running of Catalonia and halt the region's bid to declare independence.

The commission formed on Monday comprises 15 members of Spanish prime minister Mariano Rajoy's ruling Popular Party, six from the leading opposition Socialist party, and smaller parties sharing the rest.

The Article 155 measures it will study include dismissing the Catalan pro-independence regional government, including Mr Puigdemont and his ministers.

The commission is expected to notify Mr Puigdemont of its plans and invite him to defend his case, most likely by Thursday, prior to a Senate vote on Friday to activate the measures.

Mr Rajoy's party has an absolute majority in the chamber, thus guaranteeing approval.

Pro-independence students are calling for a strike in Catalan universities on Thursday to urge authorities to push ahead with a declaration of independence.

The Universities for the Republic group has staged several protests over the past month as the crisis escalated.

The group said Thursday's strike is intended to urge Catalan authorities to proclaim the Catalan Republic and defend the territory's institutions.